Polarized antenna-based MIMO for mobile terminals

The next generation of mobile communication technologies is required to ensure a high level of isolation between antennas to allow for the installation of MIMO in mobile terminals. In this paper, a MIMO antenna using polarization for use in a mobile terminal was analyzed to investigate antenna characteristics. The MIMO antenna used in this study was a square microstrip antenna on one side of 51mm to the center of the board of 200 mm × 200 mm. Power is fed to this antenna from two connectors in orthogonal positions on the microstrip line, but mutual coupling occurs between the points. To maximize isolation between ports, it is necessary to adjust the position of the feeding point. It was confirmed from the analytical results, that the electric field was distributed in two vertical regions. Therefore, a feed point, Port1, was set up at the bottom of the antenna for supplying power from the bottom. Another feed point, Port2, was set up at the point with the minimum electric field intensity. The isolation of the developed MIMO antenna is around 40dB, and the maximum cross-polarization discrimination is 26.57dB.